Why do psychologists do experiments?
Psychology is very hard to define due to it’s very nature and the wide range of topics that it covers. No two books will give exactly the same definition of ‘psychology’ or what subject matter it covers. However most definitions would suggest psychology to be the ‘scientific study of behaviour and mental processes.’ An astonishing variety of topics is covered under this definition for example topics can range from ‘obesity’ to ‘living with a divided brain’, from ‘expression of aggression’ to ‘childhood amnesia’.
No one today can afford not to know psychology as it touches every aspect of life. For example: How does the way your parents raised you affect the way you raise your kids? What effect does stress have on your immune system? How effective is psychotherapy when treating depression? How should instruments in a nuclear power station be designed to minimise human error? Can men care for infants as ably as women?
Psychologists work on these and many more questions which need to be answered as through psychological theories and research we can learn to better understand ourselves, what motivates us and how to handle situations in a better way although each situation and the individuals involved in it are unique, some things could be applied to real life. For example parents may learn that reward is better than punishment when handling their kids.
Also such theories and research have and will continue to influence laws concerning a number of areas such as capital punishment, pornography, sexual behaviour (for example sexual deviancy) However as most questions like the ones mentioned above relate to the ‘psyche’ (a totality of inner experience lacking in spatial dimensions) the problem is: How do external observers investigate someone else’s psyche systematically if they cannot understand it with their senses? Behaviourism, a movement in psychology, maintains ‘we cannot study the psyche at all because its immateriality renders it inaccessible to measurement.’ This is where experimentation comes in.
An experiment is a ‘method of investigation in which the researcher manipulates the situation in order to bring about a change in the research participant’s behaviour.’
Behaviourists, use cause-effect methodology to measure the directly observable: the environment and behaviour as this is essentially the only way one can get an insight in to the answer of any of the above questions. However many psychologists object to this exclusively behavioural definition saying that a complete denial of the psyche prevents them from making inferences about the phenomena behind behaviour. If psychologists can explain behaviour by referring to consciousness, cognition, thought or emotion, then they can risk a much richer range of predictions about behaviour. Thus many psychologists regularly construct theories about the psyche, but still choose to base them on the experimental observation of behaviour played out in measurable environmental circumstances.
Therefore experiments are essential as they allow determination of cause and affect as psychologists are interested in finding about more about human behaviour and the mental processes that underpin it. For example if we wanted to find out if “absence really does make the heart grow fonder” (Does ‘absence really make the heart grow founder?). Is it enough simply to look around and make informal observations and on that basis come to a conclusion we feel happy with? Of course in one sense it is, and as naturally inquisitive people, we do this sort of thing all the time as a means of forming our own opinions. But the fact of the matter is that such a process inevitably leads different people to different conclusions – because we each focus on different information, have different experiences, have different agendas. Thus some people think “absence really does make the heart grow fonder” while others think the opposite, that “Absence leads the heart to wander”; or “Out of sight, is out of mind”.
To know which is correct or when each is correct and, more importantly, why, we need to act as scientists, not lay-scientists. Using the scientific method to answer such questions differentiates psychology from other disciplines that address similar questions. The scientific method is a procedure for acquiring and testing knowledge through systematic observation or experimentation (e.g., through use of empirical methods) and plays an essential role in achieving the goals/objectives psychology has set out for itself.
· scientifically study behaviour and mental processes
Research is ‘any honest attempt to study a problem systematically or to add to man’s knowledge of a problem’ (Penguin Dictionary of Psychology)
The goals of psychological research are:
In order to investigate psychological theories, psychologist have a number of research methods they could use. For any method there is a compromise between conflicting advantages and disadvantages. Some of the methods available to psychologists are experimental/scientific, field experiment, natural experiment, correlation, observation, case study, survey, cross-sectional, longitudinal and cross-cultural. They are not necessarily exclusive for example you can have a cross-cultural observation.
A brief explanation of a few of the methods:-
Experimental: the relationship between two things is explored by deliberately producing a change in one variable (the independent variable, IV) and recording what effect this has on the other variable (the dependent variable, DV). This method is advantageous as it can be well controlled and replicated however it can be very artificial thus making it hard to generalise to real life.
Observational: behaviour is observed in its natural environment. All ‘variables are free to vary and interference is kept to a minimum’ No independent variable is manipulated but nevertheless a hypothesis can be tested. It is most often used with young children, wild animals, uncooperative subjects, when something is studied for the first time and when there are ethical objections to manipulating variables, e.g. looking at the effects of death. This method boasts high ecological validity and if the observer remains undetected most experimental effects are avoided e.g. experimenter bias and demand characteristics. However you can’t infer cause and effect, there are a lack of controls and it can’t be replicated.
Case Study: detailed account of a single individual: personal history, background, test results, ratings, interviews and so on. It is advantageous as it relates to real life, gives rich qualitative data and may be the only way to study atypical behaviour. On the otherhand it is time consuming and expensive, is not very scientific, is unstructured, unreplicable and unreliable. A limited sample also makes it hard to generalise to the population as a whole.
In conclusion psychologists do experiments as they are interested in finding more about human behaviour and the mental processes that underpin it. Experiments are needed in order to do this as observation is not very reliable were as experiments are scientifically based and usually allow determination of cause and affect thus helping to solve the many mysteries of life.
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